MICRO HIGH-PERFORMANCE RARE-EARTH MAGNET FOR MICRO PRODUCT AND ITS MANUFACTURING METHOD

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PROBLEM TO BE SOLVED : To provide a high-performance rare-earth magnet and a means available especially for manufacturing a small-volume rare-earth magnet and a micro motor using the same. SOLUTION : The micro high-performance rare-earth magnet for a micro product is made by mechanically working a magnet block material. Its ratio of the surface area to a volume is 2 mm-1 or more, and its volume is 100 mm3 or less. A rare-earth metal is dispersed and penetrated from the surface of the magnet to the inside thereof by a depth or equivalent to or deeper than a radius of a crystal particle exposed over the outermost surface of the magnet, so that a changed and damaged part due to the working is reformed to obtain a magnetic characteristic of 280 kJ/m3 in (BH)max. An R metal or an alloy containing the R metal that is changed into vapor or particulate in an evacuation tank by a physical method is flied on the surface of the magnet in a three-dimensional manner so as to form a film. At the same time, the R metal is dispersed and penetrated from the surface of the magnet to the inside thereof by a depth equivalent to or deeper than a radius of crystal particulate exposed over the outermost surface of the magnet.